Well, I could see how your post could be interpreted as mean-spirited. That bit about the redundant s was rather gratuitous, and you never know how sensitive someone might be about their name. On the other hand, I don't think it deserved as harsh a reply as you say you received.
Denisse, if you're still reading this thread, I've found it extremely helpful to write up a reply, then delete it, then write another one, then delete that one. By the time you're on your third draft, you'll be calm enough that you won't regret what you wrote (or realize it isn't worth replying in the first place). It's generally wise to assume that no harm was meant, unless there is no other possible interpretation of the message.
--
Jim